Low temperature poly-silicon thin film transistor (LTPS TFT) substrates can be applied on advanced display devices, e.g. liquid crystal display (LCD) devices, active-matrix organic light-emitting diodes (AMOLED), etc. In comparison to other TFTs, the low temperature poly-silicon thin film transistors have higher carrier mobility, which causes a hot carrier effect to appear, and it may even cause the thin film transistor to be invalidated.
In order to prevent the production of the hot carrier effect, when manufacturing the low temperature poly-silicon thin film transistor, a lightly doped transition region is formed by implanting ions to a source and a drain of the low temperature poly-silicon thin film transistor. However, when implanting ions to the source and the drain of the low temperature poly-silicon thin film transistor, it is difficult to form a symmetrical lightly doped transition region on both sides of the source and the drain, thereby causing that a doping concentration is deviated or a gate region is shifted.
Accordingly, it is necessary to provide a method of manufacturing thin film transistors to solve the technical problem in the prior art.